Rutgers: Optimizing Tongue Swab Testing for TB

David Alland’s group at Rutgers Medical School identified the optimal tongue swab processing method for detecting Mycobacterium tuberculosis and rifampicin resistance using Cepheid’s Xpert MTB/RIF Ultra assay, as an alternative to sputum samples.  They found that a 2:1 dilution of Xpert Sample Reagent with Tris-EDTA-Tween buffer improves the sensitivity of the Xpert Ultra assay for detecting Mycobacterium tuberculosis and rifampicin resistance in tongue swab samples compared to the commonly used heat-based protocol, and this method may enable improved sensitivity with reduced risk of over-pressurization errors, though further clinical validation is needed.

Chilambi GS, Reiss R, Daivaa N, Banada P, De Vos M, Penn-Nicholson A, Alland D. Optimal processing of tongue swab samples for Mycobacterium tuberculosis detection by the Xpert MTB/RIF Ultra assay. Microbiol Spectr. 2025 Mar 4;13(3):e0240324. doi: 10.1128/spectrum.02403-24. Epub 2025 Jan 28. PMID: 39873526; PMCID: PMC11878016.  https://journals.asm.org/doi/10.1128/spectrum.02403-24